Scheme 66

Scheme 67
Scheme 68
plus 12% epimer
Scheme 70
Scheme 71

gave the ^-C-glycoside 408 after decarboxylation [119]. Under the influence of silver ion, the displacement of the anomeric bromide in 410 with the tin acetylide shown, gave the the a product 411 exclusively. Here, the stereochemical outcome is rationalized on the basis of attack of the formed oxonium from the a face under the influence of the anomeric effect [120]. Similar chemistry has also been carried out

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